24. 336:(5x+1)=6 25. 21-(5x+14)=2499 II. Решите уравнение (самостоятельно): 1) 55-8x = 7: 2) 27: y + 29 = 38; 3) (t-25): 20 = 9; 4) 6 (18-k) = 54; 5) (60a-30): 5 = 18; 6) 92 + 56: (14 - b) = 100; 7) (c: 9) 15-47 = 28; 8) (410d): 7 + 70 = 120.

Решение:

1. 55 - 8x = 7

1. -8x = 7 - 55
2. -8x = -48
3. x = -48 / -8
4. x = 6

2. 27 : y + 29 = 38

1. 27 : y = 38 - 29
2. 27 : y = 9
3. y = 27 / 9
4. y = 3

3. (t - 25) : 20 = 9

1. t - 25 = 9 * 20
2. t - 25 = 180
3. t = 180 + 25
4. t = 205

4. 6 * (18 - k) = 54

1. 18 - k = 54 / 6
2. 18 - k = 9
3. k = 18 - 9
4. k = 9

5. (60a - 30) : 5 = 18

1. 60a - 30 = 18 * 5
2. 60a - 30 = 90
3. 60a = 90 + 30
4. 60a = 120
5. a = 120 / 60
6. a = 2

6. 92 + 56 : (14 - b) = 100

1. 56 : (14 - b) = 100 - 92
2. 56 : (14 - b) = 8
3. 14 - b = 56 / 8
4. 14 - b = 7
5. b = 14 - 7
6. b = 7

7. (c : 9) * 15 - 47 = 28

1. (c : 9) * 15 = 28 + 47
2. (c : 9) * 15 = 75
3. c : 9 = 75 / 15
4. c : 9 = 5
5. c = 5 * 9
6. c = 45

8. (410 - d) : 7 + 70 = 120

1. (410 - d) : 7 = 120 - 70
2. (410 - d) : 7 = 50
3. 410 - d = 50 * 7
4. 410 - d = 350
5. d = 410 - 350
6. d = 60

Ответ:

• 1) x = 6
• 2) y = 3
• 3) t = 205
• 4) k = 9
• 5) a = 2
• 6) b = 7
• 7) c = 45
• 8) d = 60